Spiral flame gas burner



Nov. 21, 1950 M. W.,KIRK ETAL SPIRAL FLAME GAS BURNER 2 Sheets-Sheet 1 Filed April 5, 1948 INVENTORfiy SHERWOOD lm mnla l A TTOR/VE) Nov. 21, 1950 M. w. KIRK ETAL SPIRAL FLAME GAS BURNER Filed April 5, 1948 2 Sheets-Sheet 2 Cd \Xw k W J INVENTORS M/LES W- KIRK lg ARRY 0- SHERWQOD ATTORNEY Patented Nov. 21, 1950 UNITED STATES PATENT OFFICE SPIRAL FLAME GAS BURNER Miles W. Kirk, Berkeley, and Harry 0. Sherwood,

Oakland, Calif., assignors, by mcsne assignments, to Simplex Oil Heating Corporation, New York, N. EL, a corporation of New Jersey Application April 5, 1948, Serial No. 19,108

3 Claims.

Our invention relates to fuel burners, and more particularly to a burner havin a nozzle construction adapted for both gas and fuel oil.

Because of the present scarcity of fuel oil in some localities and the scarcity of gas in others, it is desirable to enable conversion of industrial burners from gas to fuel oil or vice versa, as the conditions demand. Our invention, therefore, has as its objects, among others, the provision of an improved nozzle construction which can be readily converted from fuel oil use to gas use or vice versa; in which the gas conversion means is of efficient and improved construction; and in which the entire arrangement is of economical and simple construction. Other objects of our invention will become apparent from a perusal of the following description.

Referring to the drawings:

Fig. 1 is a more or less schematic elevational view of a conventional industrial burner arrangement embodying our improvement adapting the burner for either fuel oil or gas use; the parts being shown with the burner nozzle moved rearwardly out of firing position;

Fig. 2 is an enlarged fragmentary longitudinal sectional view illustrating portions of conventional burner parts, and our improved nozzle construction for use with gas; the position of the parts being the same as in Fig. 1;

Fig. 3 is also a fragmentary longitudinal sectional View, on the same scale as Fig. 2, illustrating the nozzle adapted for fuel oil;

Fig, 4 is an end elevation of the nozzle looking in the direction of arrow 4 in Fig. 2;

Fig. 5 is a fragmentary developed view illustrating the arrangement of spreading vanes embodied at the discharge end of the nozzle.

The burner comprises upright supporting tube 2 to which is connected a blower or fan 3, shown schematically in Fig. 1, for creating a blast of combustion air through the upright passageway 4 which is provided by upright tube 2. A suitable valve, preferably a butterfly valve 6, is provided in passageway 4 to control the flow of air. Fixed to the upper end of tube 2 is a sleeve 1 in which is sliclably mounted a horizontally positioned tube 8 at the front end of which is supported a tubular nozzle member 9 having .a relatively wide discharge opening; the tube 8 and nozzle 9 providing a horizontal passageway ll through which the blast from upright passageway 4 can flow out through the discharge end of nozzle 8. The slidable mounting of tube 8 permits the nozzle to be moved adjacent to and away from the fire box opening of the fur- 2 nace (not shown); an aperture I2 being provided in the bottom of tube 8 which registers with passageway 4 when the burner nozzle is in firing position. When the burner is not in use, tube 8 is moved out of firing position, as is shown in Fig. l, to protect the nozzle,

With reference to Figs. 2 and 3, the supporting means for nozzle 9 on tube 8 comprises sleeve [3 secured to the front end of tube 8 and which has integral therewith a spider member I4 having spaced radial spokes l6 extending from a central supporting hub member H. The rear end of nozzle membe 9 is detachably screwed onto sleeve l3 by means of screw threaded connection l3. In this connection, the spaces between spokes l6 permit the flow of air into nozzle 9.

As can be noted from Figs. 1 and 3, the means for feeding fuel oil to the burner comprise fuel inlet pipe 25 connected to fitting 22 mounted on sleeve 1, and having a suitable fuel oil control valve 23. A stationary pipe 2:3 is supported on fitting 22; and in such pipe is slidably mounted fuel feed pipe 26 which when the burner is moved to firing position slides into pipe 24, and conducts the fuel oil from fuel inlet pipe 2| toward the rear of tube 8 in which feed pipe 26 is connected to central fuel feed pipe 21 positioned internally of tube 8 and extending longitudinally thereof. Pipe 27 is screw threaded in central. hub member I! of spider l4; and the hub member is formed with a central passage 28 to permit fiow of fuel oil therethrough.

Preferably, a shutoff valve, comprising elongated stem 29 within pipe 27, is provided to close passage 28 when the burner is not in use, so that no oil can drain into the nozzle. Stem 29 has centering lugs 3! which engage the inside surface of pipe 21; and the stem extends through the rear end of the burner tube 8 where it can be operated by means of handle 32. In Fig. 1, the slidabl connection between piping 24 and 26 is shown above tube 8 for purposes of clarity, but its preferably located at the side of the tube. In this connection, the described construction is more or less conventional in fuel oil burners of the character related.

Referring to Fig. 3, a more or less conventional type of rotary fuel oil spraying cup assembly may be mounted within nozzle 9 when the burner is adapted for burning of fuel oil. Such assembly comprises stationary bearing shaft 33 having central fuel feed passageway 36 which at the front end of the shaft communicates with fuel feed discharge member 36 screwed to the 3 shaft. The rear end of shaft 33 is detachably mounted in spider hub I! by means of screw threaded connection 37.

Rotatably mounted on shaft 33 by means of a suitable bearing assembly 38 is a sleeve 39 having a plurality of circumferential impeller vanes 4i which cause rotation of the sleeve at a high speed by the air blast passing through the nozzle. Bearing assembly 38 is held in position by suitable lock nuts 42; and a fuel oil spraying cup 43 is secured to the front end of sleeve 39 by threaded connection 44. As the rotor cup assembly is rapidly rotated by the blast of air, oil fed to the interior of cup 43 from feed member 36 will be atomized by the action of centrifugal force as the oil feeds over the discharge lip 46 of cup 43 and meets the blast of combustion air passing between the cup and the inner periphery of the nozzle. For lubrication of bearing assembly 38, a passageway 41 is provided in bearing shaft 33 which communicates with passageway 48, in turn communicating with upright passageway 49 formed in one of the spokes it of the spider. Passageway 49 communicates with a lubricating oil feed pipe inside of tube 8 and which extends to the exterior of the tube. The

' rear end of pipe 51 is provided with suitable lubricating oil fitting (not shown).

From the preceding, it is seen that the rotor cup assembly can be readily detached by unscrewing nozzle 9 from sleeve l3, and unscrewing bearing shaft 33 from hub ll of the spider. Attachment can be readily effected in a reverse manner. As is usual in oil burners of the character related, any suitable automatic control means may be provided for correlating the flow of fuel oil past valve 23 and the flow of air past valve 5 when the burner is in operation, in accordance with firing conditions required.

For adapting the burner for use with gas, we employ a special vane arrangement internally of the discharge end of nozzle, which serves to throttle a flowing mixture of gas and air as it is discharged from the nozzle by imparting a change in direction to the flow, to thus cause the flame of the ignited mixture to be held adjacent the discharge end of the nozzle. Such vane arrangement is also eflicaciously operable with the fuel oil adaptation previously described. In conjunction with this vane arrangement, we employ a special deflecting means for directing the flowing mixture of gas and air toward the vanes, and which can readily replace the fuel oil rotor cup assembly. With reference to Fig. 2, the discharge end of nozzle 9 is formed with an inwardly curved discharge lip El; and a plurality of spaced throttling vanes 62 extend inwardly of the nozzle from such discharge lip, the vanes being wider than the discharge lip, so that their inner edges 63 extend radially inwardly beyond the inner periphery of the discharge lip.

To throttle the blast, a spiral effect is imparted thereto by having the vanes angularly inclined with respect to the longitudinal axis of the nozzle. The angle of the vanes may be, preferably, anywhere between 30 and 50 with reference to such longitudinal axis but a most suitable angle is 45; and as can be noted from the developed view of Fig. 5, the vanes are so spaced apart that the front end of each vane overlaps the rear of an adjacent vane. By such arrangement in cooperation with discharge lip 6 i, all the blast must be directed spirally outwardly of the nozzle by the vanes, as there is no straight path therethrough, and the flame will be held adjacent the discharge end of the nozzle. Without the throt tling effect, the mixture of gas and air could be ignited only with difficulty, if at all; and if ignited, the resultant flame would burn at a distance widely spaced from the nozzle, which is undesirable.

For introduction of gas to be mixed with the air, we find it extremely important that the gas be introduced by inlet connection 64 in upright passageway 4 and below horizontal passageway II, and preferably between butterfly valve 6 and horizontal passageway H. Introduction of the gas at this point results in thorough and eiflcacious mixing of the gas and the air by the turbulence created, as the blast changes direction as it flows from upright passageway l at right angles into horizontal passageway l l. The mixture of gas and air flows between the spokes l6 of the spider; and to provide for efiicient combustion of such gas and air mixture, we employ special deflecting means at the rear of the vanes for directing the mixture toward the vanes.

Such deflecting means comprises cone shaped deflector 65 which has an axially adjustable screw threaded connection 66 on a rod El, in turn mounted on a boss 68 adapted for detachable screw threaded connection 69 in hub ll of the spider, in place of the shaft 33 of the rotor assembly. It is important for obtaining a proper flame, that the deflector be relatively closely positioned adjacent the rear ends of the vanes and that the slope of the cone be such as to direct the flowing mixture of gas and air toward the inner periphery of the nozzle within the area A occupied by the vanes as is indicated by the phantom line L in Fig. 2. Threaded connection 66 of cone 65 on rod 67 provides for the axial adjustment of the cone to obtain the desired regulation of the distance between the cone and the vanes; the cone being held in the desired adjusted position by a lock nut H. The slope of the cone may be any suitable angle as long as it is such as to provide the described effect within reasonable limits of adjustment; a desirable angle being about 30. It is to be noted that the diameter of the base of cone deflector 65 is less than the diameter defined by the inner peripheral edges 63 of the vanes; so that a small radial spacing exists between the base of the cone and the inner edges 63 of the vanes.

By the described arrangement including inwardly extending lip 6i, the inclined throttling vanes 62, and the adjustable deflecting cone 65 spaced slightly rearwardly of the vanes, the flame of the burning mixture of gas and air, which may be ignited by any suitable means, will be held within the furnace adjacent the discharge end of the nozzle. An analogous effect obtains when the burner is adapted for oil combustion, as the same vaned nozzle is employed for both gas and oil fuel. Thus, as the blast of air flows past rotary cup 43 it mixes with the oil sprayed from the cup; and the described vane and lip arrangement, serves to provide for proper flame regulation.

Because both the gas deflector assembly and the rotor cup assembly can be quickly and easily mounted on spider 54, merely by removal of nozzle 9, attaching the desired assembly, and replacing the nozzle, it is seen that conversion from one to the other may be readily effected. In this connection, when operating with gas, the mixture of gas and air may be automatically controlled by any suitable automatic control mechanism in accordance with firing conditions, fo correlating the operation of air valve 6 with gas valve 12 provided for inlet connection 64.

We claim:

1. A burner comprising a nozzle adapted to receive a flowing mixture of gas and air and having an inside cylindrical surface portion adjacent the discharge end thereof, substantially straight vanes fixed to the inside of said cylindrical portion of the nozzle at the discharge end thereof and inclined with respect to the axis of the nozzle,

the ends of said vanes adjacent said nozzle discharge end extending substantially to said discharge end and projecting radially inwardly of said nozzle at said nozzle discharge end and the inner peripheral edges of said vanes lying on substantially the same cylindrical surface, and a cone shaped deflector spaced permanently rearwardly from but closely adjacent the rear ends of said vanes, the cone sloping outwardly with reference to said nozzle discharge end at such angle as to direct the mixture toward the inner periphery of said nozzle within the area occupied by said vanes, the diameter of the base of said cone shaped deflection being less than the diameter defined by the inner peripheral edges of the vanes whereby radial clearance exists between the periphery of the base of said cone and the inner edges of said vanes.

2. A burner comprising a nozzle adapted to receive a flowing mixture of gas and air and having an inside cylindrical surface portion adjacent the discharge end thereof, the discharge end of said nozzle having an inwardly extending discharge lip, substantially straight vanes fixed to the inside of said cylindrical portion of the nozzle at the discharge end thereof and inclined with respect to the axis of the nozzle, the ends of said vanes adjacent said nozzle discharge end extend ing substantially to said discharge end lip and projecting radially inwardly of said nozzle at said nozzle at said discharge end lip and the inner peripheral edges of said vanes lying on substantially the same cylindrical surface, and a cone shaped deflector spaced permanently rearwardly from but closely adjacent the rear ends of said vanes, the cone sloping outwardly with reference to said nozzle discharge end at such angle as to direct the mixture toward the inner periphery of said nozzle within the area occupied by said vanes, the diameter of the base of said cone shaped deflector being less than the diameter defined by the inner peripheral edges of the vanes whereby radial clearance exists between the periphery of the base of said cone and the inner edges of said vanes.

3. A burner comprising a generally horizontal ly extending passageway adapted to receive a flowing mixture of gas and air, an upright passageway adapted to conduct a blast of air to said horizontal passageway, a valve in said upright passageway for controlling the flow of air, a gas inlet in said upright passageway between said air control valve and said horizontal passageway, said horizontal passageway terminating in a nozzle having an inside cylindrical surface portion adjacent the discharge end thereof, substantially straight vanes fixed to the inside of said cylindrical portion of the nozzle at the discharge end thereof and inclined with respect to the axis of the nozzle, the ends of said vanes adjacent said nozzle discharge end extending substantially to said discharge end and projecting radially inwardly of said nozzle at said nozzle discharge end and the inner peripheral edges of said vanes lying on substantially the same cylindrical surface, and a cone shaped deflector spaced permanently rearwardly from but closely adjacent the rear ends of said vanes, the cone sloping outwardly with reference to said nozzle discharge end at such angle as to direct the mixture toward the inner periphery of said nozzle within the area occupied by said vanes, the diameter of the base of said cone shaped deflector being less than the diameter defined by the inner peripheral edges of the vanes whereby radial clearance exists between the periphery of the base of said cone and the inner edges of said vanes.

MILES W. KIRK. HARRY O. SHERWOOD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 982,584 Frink Jan. 24, 1911 1,740,985 Irish Dec. 24, 1929 1,950,800 Kerr Mar. 13, 1934 1,991,942 Clark Feb. 19, 1935 2,118,228 Ravenna May 24, 1938 2,153,497 Betzold Apr. 4, 1939 2,233,529 Herr Mar. 4, 1941 FOREIGN PATENTS Number Country Date 231,731 Great Britain Apr. 9, 1925 308,054 Great Britain Mar. 21, 1929 

